1. In a large nonstick skillet coated with cooking spray, sauté the onion, celery, and peppers in oil until crisp-tender.

2. Add garlic; cook 1 minute longer.

3. Stir in the chicken, soups, tomatoes, and chili powder.

4. Line the bottom of a 3-qt. baking dish with half of the tortilla strips; top with half of the chicken mixture and 1 cup cheese. Repeat layers. Bake, uncovered, at 350° for 30-35 minutes or until bubbly.